Oximino phosphates and phosphonates

ABSTRACT

COMPOUNDS HAVING THE FORMULA   R-O-C(-5-R1)=N-O-P(=X)(-R2)-Y-R3   IN WHICH X IS OXYGEN OR SULFUR; Y IS OXYGEN OR SULFUR; R IS ALKYL; R1 IS ALKYL; R2 IS ALKYL OR ALKOXY AND R3 IS (1) PHENYL, OR (2) MONO-, DI OR TRI-DUBSTITUTED PHENYL WHEREIN THE SUBSTITUENT IS (A) NITRO OR (B) HALOGEN, AND THEIR USE AS INSECTICIDES, AND ACARICIDES ARE DISCLOSED. ALSO, THE INTERMEDIATES FOR PREPARING THE COMPOUNDS AND A METHOD FOR PREPARING THE INTERMEDIATES ARE DISCLOSED.

United States Patent Oflice 3,660,541 Patented May 2, 1972 3,660,541OXIMINO PHOSPHATES AND PHOSPHONATES Arnold D. Gutrnan, Berkeley, Calif.,assignor to Staulfer Chemical Company, New York, N.Y.

No Drawing. Filed Apr. 6, 1970, Ser. No. 26,070 Int. Cl. C07f 9/16; A01n9/36 U.S. Cl. 260-944 3 Claims ABSTRACT OF THE DISCLOSURE Compoundshaving the formula This invention relates to certain novel chemicalcompounds, novel intermediates for their preparation, the use of thechemical compounds as insecticides and acaricides and to a process forpreparing the intermediates. More particularly, the chemical compoundsare certain phosphorus containing compounds.

The compounds of this invention are those having the formula X YR ll/ inwhich X is oxygen or sulfur; Y is oxygen or sulfur;

R is (1) alkyl having 1 to 4 carbon atoms, preferably branched chain ormethyl, more preferably ethyl and t-butyl;

R is alkyl having 1 to 4 carbon atoms, preferably methyl;

R is alkyl having 1 to 4 carbon atoms, preferably 1 to 2 carbon atoms;or alkoxy having 1 to 4 carbon atoms, preferably 1 to 2 carbon atoms;

R is (1) phenyl or (2) mono-, dior tri-substituted phenyl wherein thesubstituent is (a) nitro or (b) halogen, preferably chlorine, preferablymono substitution is in the meta or para positions and the substituentis halogen or nitro, di-substitution is meta and para or ortho and paraand the substituents are both halogen groups and tri-substitution is inthe 2,4,5 position and the substituents are all halogen, preferablychlorine. Optional- 1y, such groups as alkyl having 1 to 4 carbon atomsor (h) alkoxy having 1 to 4 carbon atoms may also be substituted on thephenyl, preferably in the meta position.

The compounds of the present invention can be prepared according to thefollowing reactions: 1(a) R X 01 R0 x O] C=NOH Cll B- \C=NO i R18 R R 8R 1 1) RO\ INC/Cl NaOH R0\ J C/YRa C=NOP HYR3 o=NOP R s R R 8 YR inwhich R, R R R X and Y are as defined.

The process of this invention is represented by reaction 1(a) and :givesthe novel intermediates of this invention. In other words, the processis for preparing a compound having the formula no X 01 C=NOl R S R2 inwhich R, R R and X are as defined comprising reacting a compound of theformula in which R and R are as defined with a compound of the formulain which R and X are as defined.

The compound recited in reaction 1(a) and I(b) where R and R are asdefined can be prepared according to the general procedure stated inBelgium Pat. No. 710,649, by reaction of the appropriate xanthate, withhydroxyl amine hydrochloride followed by reaction with the appropriatealkyl halide.

Preferably, reaction 1(a) is carried out by reacting preferably equalmole amounts of the two reactants. If an excess of either reactant isused, the reaction still proceeds but yields are reduced. The reactantscan be combined in any desired manner but preferably, the reaction isrun in a. solvent such as THF by first preparing the salt of the oximereactant with an acid acceptor such as potassium t-butoxide at roomtemperature, and then preferably slowly adding the dichloride reactantthereto, preferably in solution with a solvent, for example, THF, at atemperature below about 15 C. for control. However, the oxime reactantcan be used in place of the salt, preferably in the presence of the acidacceptor. The resulting product is recovered and purified by standardprocedure. For example, the resulting product can be recovered from thereaction mixture and purified from the reaction mixture by adding themixture to a non-polar solvent such as benzene. The benzene mixture isthen washed with water, dilute NaOH solution, and then again by water.The benzene is evaporated after the water has compounds of thisinvention, for example, by reaction I(b), heretofore described are thosehaving the formula in which X is oxygen or sulfur; R is alkyl having 1to 4 carbon atoms, preferably branched chain or methyl, more preferablyethyl and t-butylpR is alkyl having 1 to 4 carbon atoms, preferablymethyl; R is alkyl having 1 to 4 carbon atoms, preferably 1 to 2 carbonatoms; or alkoxy having 1 to 4 carbon atoms, preferably 1 to 2 carbonatoms. These intermediate compounds can be prepared according toreaction 1(a) specifically described heretofore.

The reaction, reaction I(b), is carried out by reacting preferably equalmole amounts of the two reactants. If an excess of either reactant isused, the reaction still proceeds but yields are reduced. The reactantscan be combined in any manner but preferably the phosphorus-containingreactant is slowly added to the phenol or thiophenol reactant in asolvent such as THF, preferably with stirring. More preferably, analkali metal salt of the phenol or thiophenol salt is used to reduce thechance of a violent reaction. The temperature of the reaction is notcritical, however, better yields are obtained by heating the reactantsat reflux for a time sufiicient to allow completion of the reaction. Theresulting product can be recovered from the reaction mixture andpurified by standard procedures. For example, the desired reactionproduct can be recovered from the reaction mixture by adding the mixtureto a non-solvent such as benzene. The benzene mixture is then washedwith water, dilute NaOH solution and then' again by water. The benzeneis evaporated after the water has been removed, for example, bytreatment with anhydrous MgSO, to yield the purified product.

Preparation of the compounds of this invention and the intermediatecompounds of this invention are illustrated by the following examples:

EXAMPLE I EtO SCI

ll/ C=NOP -(O-ethyl S-methylthioformaldoximino), ethyl thiophosphonylchloride 22.4 grams (0.2 mole) of potassium t-butoxide is:combined with500 ml. of tetrahydrofuran, in a 1 l. beaker and 27.0 grams (0.2 mole)of 'O-ethyl, methylthioformaldoxime is added. The mixture is stirred atroom temperature for minutes. 32.6 grams (0.2 mole) ofethylyphosphonothionic dichloride is combined with 200 ml.oftetrahydrofuran in a 1 liter three-neck flask fitted with a stirrer,thermometer and dropping funnel. The solution is cooled in an ice bathand stirred. The oxime salt solution is added over a period of 15minutes at such a rate that the temperature does not exceed 15 C. Afterthe addition is complete, the resulting mixture is stirred at roomtemperature for one hour, then poured into 400 ml. of benzene. Thebenzene mixture is washed with two 300 ml. portions of H 0, dried withanhydrous MgSO and evaporated under reduced pressure to yield 46.0 grams(88.3% of theory) of O-(O-ethyl-S-methylthioformaldoximino), ethyl,thiophosphonyl chloride, N =1.5370. The compound is characterized by IR.

4 EXAMPLE II Et0\ i O@ N02 C=NOP OHBS 2 s0-(0-ethyl-S-methylthioforma1doximino),ethyl-(4-nitrophenyl)thionophosphonate 7.0 grams (0.0503 mole) of4-nitrophenol is combined with 2.1 grams (0.0503 mole) of caustic and 25ml. of water in a 500 ml. three-neck flask fitted with a stirrer,thermometer, and dropping funnel. The mixture is stirred and 11.5 grams(0.0503 mole) of O-(O-e-thyl-S-methylthioformaldoximino),ethylthiophosphoryl chloride, obtained in Example I, in 200 ml. oftetrahydrofuran is added over a period of 30 minutes. The resultingmixture is stir-red and heated under reflux for two hours, cooled andpoured into 300 ml. of benzene. The benzene mixture is washed with 200ml. of H O, 200 ml. dilute NaOH solution, followed by two 200 ml.portions of H 0. The benzene is dried with anhydrous MgSO and evaporatedto yield 11.5 grams (63.1% of theory) of the desired compound,O-(O-ethyI S-methylthioformaldoximino), ethyl-(4-nitrophenyl)-thiophosphon-ate. The compound is characterized by IR. N==1.'5670.

EXAMPLE III EtO CH;S/ O 02H;

0-(O-ethyl-S-methylthioformaldoximino) O-ethyl phosphoryl chloride 16.3grams (0.1 mole) of ethyldichlorophosphate is combined with 20 ml. oftetrahydrofuran in a 250 ml. three-neck flask fitted with a stirrer,thermometer and dropping funnel. The solution is stirred and cooled to'-10 C. A solution of 13.5 grams (0.1 mole) of O- ethyl,methylthioformaldoxime, 4.0 grams (0.1 mole) of caustic, and 20 ml. ofwater is added to the stirring solution over a period of 30 minutes. Theresulting mixture is stirred for one hour at 0 C. and 30 minutes at roomtemperature until the mixture becomes neutral to pH paper. The mixtureis then poured into 300 ml. of Et O and is washed with two ml. portionsof H 0. The Et O phase is dried with anhydrous MgSO; and evaporated toyield 25.0 grams (96.1% of theory) of the desired complgund. N :1.4795.The structure is characterized by EXAMPLE IV 21150 O O N n/ C=NOP CH SOCzHs 0-(O-ethyl-S-methylthioformaldoximino), O-ethyl-O-(3-methyl-4-nitrophenyl) phosphate 11:31 grams (0.05 mole) of0-(O-ethylmethylthioformaldOXlmIIIO), O-ethyl phosphoryl chlorideobtained in Example III is reacted with 7.65 grams (0.05 mole) of 3-methyl-4-nitrophenol and 2.1 grams (0.0503 mole) of caustic in the samemanner as Example II to yield 9.5 grams (50.2% of theory) of the desiredcompound. N 1.5254. The compound is characterized by IR.

The following is a table of certain selected compounds that arepreparable according to the procedure described hereto. Compound numbersare assigned to each compound and are used throughout the remainder ofthe application.

TABLET RO\ INK/YR C=NOP RS R Compoundnumber R R R X Y R N];

1 CzHs CH3 O2H5 S CH 1.5604

2 CzHs CH3 CzHs S 0 1.5670

3 CzHs CH3 Cal-Is S S Q 1.5913

4 C2H CH3 CzHs S O (31 1.5675

5 C2115 CH3 --OC2H5 O 0 EH: 1.5254

6 CzHs CH3 -OC2H5 O 0 01 1.5290

Prepared in Example II. Prepared in Example IV.

The following tests illustrate the insecticidal and acaricidal activityof the compounds of this invention.

INSECTICIDAL EVALUATION TESTS The following insect species were used inevaluation tests for insecticidal activity:

(1) Housefly (HF)-Musca domestica (Linn.)

(2) German Roach (GR)-Blatella germanica (Linn.)

(3) Salt-Marsh Caterpillar (SMC) -Estigmene acrea (4) Lygus Bug(LB)-Lygus hesperus (Knight) (5) Bean Aphid (BA)-Aphis fabae (Scop.)

The Housefiy (HF) was used in evaluation tests of selected compounds asinsecticides by the following procedure. A stock solution containing 100ugjml. of the toxicant in an appropriate solvent was prepared. Aliquotsof this solution were combined with 1 milliliter of an acetone-peanutoil solution in an aluminum Petri dish and allowed to dry. The aliquotswere there to achieve desired toxicant concentration ranging from 100,ug. per dish to that at which 50% mortality was attained. The disheswere placed in a circular cardboard cage, closed on the bottom withcellophane and covered on top with cloth netting. Twenty-five femalehouseflies, three to five days old, were introduced into the cage andthe percent mortality was recorded after 48 hours. The LD values areexpressed in terms of g. per female flies. The result of theseinsecticidal evaluation tests are given in Table II under 6HF.9

In the German cockroach (GR) tests, 10 one-month old nymphs were placedin separate circular cardboard cages sealed on one end with cellophaneand covered by a cloth netting on the other. Aliquots of the toxicants,dissolved in an appropriate solvent, were diluted in water containing0.002% of a wetting agent, Sponto 22l, (a polyoxyether of alkylatedphenols blended with organic sulfonates). Test concentrations rangedfrom 0.1% downward to that at which 50% mortality was obtained. Each ofthe aqueous suspensions of the candidate compounds was sprayed onto theinsects through the cloth netting by means of a hand-spray gun. Percentmortality in each case was recorded after 72 hours, and the LD valuesexpressed as percent of toxicant in the aqueous spray were recorded.These values are reported under the columns GR in Table II.

For testing the salt marsh caterpillar, test solutions were prepared inan identical manner and at concentrations the same as for the Germancockroach above. Sections, of bitter dock (Rumex obtusifolus) leaves,1-1.5 inches in length, were immersed in the test solutions for 10 to 15seconds and placed on a wire screen to dry. The dried leaf was placed ona moistened piece of filter paper in a Petri dish and infested with5-3rd Instar larvae. Mortality of the larvae was recorded after 72 hoursand the LD values are expressed as percent active ingredient in theaqueous suspension.

T he lygus bug (LB) Lygus hesperws was tested similarly as the Germancockroach. The caged insects were sprayed with the candidate compoundsat concentrations ranging from 0.05% downward to that at which 50%mortality was obtained. After twenty-four and seventy-two hours, countswere made to determine living and dead insects. The LD (percent) valueswere calculated. These values are reported under the column LB in TableII.

The insect species black bean aphid (BA) Aphis fabae (Scop.)was alsoemployed in the test for insecticidal activity. Young nasturtium(Tropaeolum sp.) plants, approximately 2 to 3 inches tall, were used asthe host plants for the bean aphid. The host plant was infested withapproximately 50-75 of the aphids. The test chemical was dissolved inacetone, added to Water which contained a small amount of Sponto 221, anemulsifying agent. The solution was applied as a spray to the infestedplants. Concentrations ranged from 0.05 percent downward until an LDvalue was achieved. These results are given in Table II under the columnBA.

ACARICIDAL EVALUATION TEST The two-spotted mite (28M), Tetranychusurticae (Koch), was employed in tests for miticides. Young pinto beanplants or lima bean plants (Phaseolus sp.) in

the primary leaf stage were used as the host plants. The young pintobean plants were infested with about 100 mites of various ages.Dispersions of candidate materials were prepared by dissolving 0.1 gramin ml. of a TABLE II.LD VAL UES Two-spotted mites HF, GR, LB, SMG, BA,BA-sys, PE, Eggs, Sys,

Compound number g. percent percent percent percent; p.p.m. percentpercent ppm.

suitable solvent, usually acetone. Aliquots of the toxicant solutionswere suspended in water containing 0.002% v./v. Sponto 221,polyoxyethylene ether sorbitan monolaurate, an emulsifying agent, theamount of water being sufficient to give concentrations of activeingredient ranging from 0.05% to that at which mortality was obtained.The test suspensions were then sprayed on the infested plants to thepoint of run off. After seven days, mortalities of post-embryonic andovicidal forms were determined. The percentage of kill was determined bycomparison with control plants which had not been sprayed With thecandidate compounds. The L values was calculated using well-knownprocedures. These values are reported under the columns ZSM-PE and 28M-Eggs in Table II.

SYSTEMIC EVALUATION TEST This test evaluates the root absorption andupward translocation of the candidate systemic compound. The two-spottedmite (2SM), Tetranychus urticae (Koch) and the bean aphid (BA), Aphisfabae (Scop.) were employed in the test for systemic activity.

Young pinto bean plants in the primary leaf stage were used as hostplants for the two-spotted mite. The pinto bean plants were placed inbottles containing 200 ml. of the test solution and held in place withcotton plugs. Only the roots were immersed. The test solutions wereprepared by dissolving the compounds to be tested in a suitable solvent,usually acetone, and then diluting with distilled water. The finalacetone concentration never exceeded about 1 percent. The toxicants wereinitially tested at a concentration of 10 parts per million (ppm).Immediately after the host plant was placed in the test solution it wasinfested with the test species. Mortalities were determined after sevendays.

Young nasturtium plants were used as the host plants for the bean aphid.The host plants were transplanted into one pound of soil that had beentreated with the candidate compound. Immediately after planting in thetreated soil the plants were infested with the aphids. Concentrations oftoxicant in the soil ranged from 10 ppm. per pound of soil downwarduntil an LD value was obtained. Mortality was recorded after 72 hours.

The percentage of kill of each test species was deter- As those in theart are well aware, various techniques are available for incorporatingthe active component or toxicant in suitable pesticidal compositions.Thus, the pesticidal compositions can be convienently prepared in theform of liquids or solids, the latter preferably as homogeneousfree-flowing dusts commonly formulated by adnn'xing the active componentwith finely divided solids or carriers as exemplified by talc, naturalclays, diatomaceous earth, various flours such as walnut shell, wheat,soya bean, cottonseed and so forth.

Liquid compositions are also useful and normally comprise a dispersionof the toxicant in a liquid media, although it may be convenient todissolve the toxicant directly in a solvent such as kerosene, fuel oil,xylene, alkylatednaphthalenes or the like and use such organic solutionsdirectly. However, the more common procedure is to employ dispersions ofthe toxicant in an aqueous media and such compositions may be producedby forming a concentrated solution of the toxicant in a suitable organicsolvent followed by dispersion in water, usually with the aid of surfaceactive agents. The latter, which may be the anionic, cationic, ornonionic types, are exemplified by sodium stearate, potassium oleate andother alkaline metal soaps and detergents such as sodium lauryl sulfate,sodium naphthalene sulfonate, sodium alkyl naphthalene, sulfonate methylcellulose, fatty alcohol ethers, polyglycol fatty acid esters and otherpolyoxyethylene surface active agents. The proportion of these agentscommonly'comprises 1-15 by weight of the pesticidal compositionsalthough the proportion is not critical and may be varied to suit anyparticular situation.

I claim:

1. A compound having the formula RO\ )fli/Y-Ra C=NOP in which X isoxygen or sulfur; Y is oxygen or sulfur; R is alkvl having 1 to 4 carbonatoms; R is alkyl having 1 to 4 carbon atoms;

10 R is alkyl having 1 to 4 carbon atoms, or alkoxy hav- ReferencesCited ing 1 4 UNITED STATES PATENTS 3 R p11; n; i) phenyl (2) mtrophenylor (3) trlchloro 2,816,128 12/1957 Alled n 260 944 UX 2. The compound ofclaim 1 in which R is ethyl, R 5 LEWIS GOT-TS P Ex is methyl, R isethyl, X is sulfur, Y is oxygen, and R is anfmer A it h L A. H. SU ITO,Assistant Exammer 3. The compound of claim 1 in which R is ethyl, R U SCl X R is methyl, R is ethyl, X is sulfur, Y is sulfur and R isophenyl.10 260-968, 973; 424210

